sudmann



(No Model. 3 Sheets-Sheet 1.

J. SUDMANN.

METALLIC THERMOMETER.

No. 398,755. Patented Feb. 26, 1889.

\fitnesses Invent 01" $upiMAaM u 3 Sheets-Sheet 2.

(No Model.)

' J. SUDMANN.

METALLIC THERMOMETER.

Patented Feb.26, 1889.

01 Witnesses, 7?

Inventcnm 3 Sheets-$het 3.

(No Model.)

J. SUDMANN.

METALLIG THERMOMETER.

No. 398,755. Patented Feb. 26, 1889'.

In've nt 01" Witnesses Emma/M114,

Nrrrin stares PATENT OFFICE,

JOHAXN SUDMANN, OF HAMBURG, GER-MANY.

METALLIC THERMOMETER.

SPECIFICATION forming part of Letters Patent No. 398,755, dated February 26, 1889.

Application filed December 12,1887. serial No. 257,656 (No model.)

To aZZ 10700777; it may concern:

Be it known that I, JOHANN SUDMANN, a

subject of the Emperor of Germany, and a resident at l'lan'iburg, in the German Empire, have invented certain new and useful. llllprovements in Metallic which the following is a specification.

This invention relates to that class of thermometers in which the change of temperature in the surrounding air is ascertained by the unequal expansion of different metal strips soldered together; and the objects of my said invention are, first, to afford means for securing the invariable transmission of the deflection of the compensating strips upon the dialwork in ilependently of the position of the thermometer; second, to provide straight compensating strips for the thermometer; third, to arrange the drivin mechanism independently of the dial-work for the purpose of employing a throughout uniformly-divided scale and to regulate the degree of oscillation of the pointer in accordance with the division of the dial plate or scale in the thermometer, and,

fourth, to provide means for adjusting the Similar-letters refer to similar parts throughout the several views.

The thermon'leter shown in the drawings is provided with two straight thermometric 'lhcrnuanctcrs, of

' uniform, (as far as the deflection of the strips strips, (1, which are preferable in case the instrument is to be used for scientific obser- 'ations,while for ordinary use one strip only Those thermometrie strips l the pinion. 71: on the spindle of the pointer Z by means of av pair of fork-shaped drivers, 0 c, into which engages the pin 7. adj u stably gui ded lrv the screw /1 in a notch of the sector 1.'.

As the motion imparted to the driving-disk by the dclleclion of the strips is throughout may be considered as increasing continuously and in direct proportion with the augmentation of the temperature of the surrounding air,) the division of the scale can be made equidistant and independently from the dialwork, provided that the degree of oscillation of the pointer can be adjusted. Hower'er, the adjustment may be easily effected by varying the distance of the pins t of the said drivingdisk in relation with the center of oscillation of the latter; but when employing two strips a uniform radial movement of both the pins i will be necessary, and therefore underneath of the driving-disk d a corrcspondin g disk, d, is jointed, which is provided (equidistant from the center of the driving-disk) with two slots, 1:, crossing the radial slots t of the driving disk (I, into which engage the pins 1; and it will be clearly understood from the drawings, Figs. 7 and 8, that the turning of the lower plate, d, relatively to the disk (I will cause the pins t to move uniformly in the radial slots 1' of driving-disk (Z. Thus the distance from the center of oscillation of the pins 2, which are connected by the pitmen c c with the strips, may be varied ad Zibz'tum within certain limits, and consequently the angle of oscillation of the drivers 0 c and of the pointer may be easily regulated in accordance with the scale of the dial-work.

In order to adjust the pointer without affecting the driving mechanism, the frame 1) of the dial-work is mounted on a separate bedplate, B, fixed to the case of the thermometer, while the frame A, with the driving mechanism, is adapted to swing around a pivot, n, of the said stationary bed-plate B. The declination of the center line of the frame A from that of the bedplate B is governed by an eccentric, 0, Fig. 3, or a similar device, from the outside of the thermometercase. As the frame p of the dial-work, by means of the bracket 2', eccentrically arranged to the pivot n, is firmly connected with the stationary bedplate 13, the frame A will turn around the pivot at under the influence of the eccentric 0, engaging into a notch, s, of the frame A. In consequence of the turning of the frame of I the driving-work independently from the stationary tram e of the d ia l-work the fork-shaped driver 0 c of the crank-disk (Z will take with it the pin 7, acting upon, the sector 1', and the E f'dicatorand its gearing mounted upon said support, a-disk operating said gearing and havin'gthefork-shaped drivers 0 a, pin Z, and the pitman-conn ection between said drivers and-metallic strip, substantially as set "fortliz i, t

2& 111a metallic thermometer, the combinationof the pinslwith the driving-disk d, havin radial slots o, the movable plate d, provided with slots 1!, crossing those of the driving-disk, the pitmen e e, and the thermomet ric strips, substantially as set forth, and For the purpose specified.

3. The combination, in a thermometer, of the movable frame A, thermometric strip connected at one end to the same, disk having the other end of said strip connected thereto, gearing and pointer operated by said disk, and the stationary bed-plate B, carrying the dial- Work, substantially as set forth.

4. In a metallic thermometer having the driving mechanism secured to a movable frame, A, and the dial-work mounted on a stationary bed-plate, B, the combination of the eccentric 0 with the said stationary bed-plate and the said movable frame A, substantially as set forth, and for the purpose specified.

In testimony that I claim the foregoing as my invention I have signed my name, in presence of two witnesses, this 27th day of October, 1887.

J OI-IANN SUDMANN.

\Vitnesses:

ALEXANDER SPECHT, DIEDRIOH PETERSEN. 

